Brace-chuck



UNITED STATES PATENT OFFIGEO JOHN S. FRAY, OF BRIDGEPORT, CONNECTICUT.

BRACE-CHUCK.

SPECIFICATION forming part of Letters Patent No. 395,222, dated December 25, 1888.

Application filed November 10, 1838, Serial No, 290,423. No model.)

To aZZ whom it may concern:

Be it known that I, JOHN S. FRAY, a citizen of the United States, residing at Bridgeport, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Brace-Chucks; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention has for its object to simplify the construction and at the same time to greatly improve the operation of this class of devices in use.

\Vith these ends in vicwl have devised the novel improvements in the construction, adjustment, and mode of operation of the spring which opens the jaws when the sleeve is turned outward, of which the following description, in connection with the accompanying-drawings, is a specification, numbers being used to denote the several parts.

Figure l is an elevation of an ordinary ratchct -brace, the sleeve and head being in section and the jaws and jaw-spring in elevation, the position of the parts being that in which a bit-shank is clamped and tightly held by the jaws; Fig. '3, a section, on an enlarged scale, of the jaws detached, the spring being in elevation and the jaws of course at their open position; and l ig. 3 is an elevation of the jaws and spring, also in the open position.

1 denotes the brace, '3 the stock, I} the head, and t the shank, made integral with or rigidly secured to the head and extending up through the stock in the usual manner. .These parts may all be of the usual or any preferred construction, and form no portion of my present invention.

5 denotes the jaws, which are provided with inclines 6 at their bases and with inclines 7 at their outer ends.

8 denotes the sleeve, which is provided with an internal screw-thread, 9, adapted to engage a correspont'ling external screw-thread upon the head. The inclines (3 at the bases of the Upon the inn er side of the sleeve, at its outer end, is an incline, 12, which is engaged by the inclines 7 at the outer ends of the jaws. It will therefore be seen that when the sleeve is turned inward that is, toward the stock-all of the inclines are caused to engage and the jaws are caused to adapt themselves to the special shape of any bit-shank that has been placed between them and to clasp and hold it firmly, incline 12 acting to force the jaws inward, and at the same time to close their outer ends together, and incline l0 acting to close the bases of the jaws together.

1? denotes the jaw-spring, which I make substantially U shape, the curve being fiattened, as shown in the drawings. The central portion of this spring-that is, the flattened portion of the cur\"epas through openings 14 in the bases of the jaws, and the ends thereof engage the forward ends of the jaws, holes l5 being preferably made in the jaws and the ends of the spring sprung into place, so that in use it is practically impossible for the spring to become detached. In order that the bases of the jaws may have ample movement I provide a recess, 1! in the back of each jaw, in which the spring lies when the bases of the jaws are pressed apart or are adjusting themselves to the shank of a bit or other tool. This gives to the jaws the entire internal dian'ieter of the sleeve to work in. This construction of spring I [ind to work admirabl y in practice, as it holds the jaws againstendwise movement, except as they move together, it throws the outer ends of the jaws to their open posit-ion and holds them there when the sleeve is turned outward, and at the same time it leaves the bases of the jaws free to slide in or out and to adapt themselves to different shapes of tangs or shanks of bits or other tools.

Having thus described my invention, I claim- 1. In a brace-chuck, the jaws having openings attheir bases, in combination with a spring the central portion of which passes through said openin and the ends of which. engage the forward ends of the jaws.

In a brace-chuck, the jaws having openings at their bases and holes at their forward ends, in combination with a U-shaped spring the central portion of which passes through the openings in the bases of the jaws and the ends of which engage the holes at the forward ends thereof, as and for the purpose set forth.

3. The head having incline 10 and a sleeve having incline 12, in. combination with the jaws having inclines engaging the inclines upon the head and the sleeve, openings through their bases, and a spring which passes through said openings and engages the outer ends of the jaws, whereby the jaws are held against independent endwise movement, the,

outer ends of the jaws are opened when the sleeve is turned outward, and the inner ends are caused to adapt themselves to the shape of the bit-shank and are closed upon it when the sleeve is turned inward.

4. The sleeve and the jaws having openings at their bases and holes at their forward ends, in combination with a spring which passes through said openings and whose ends engage said holes, whereby the spring and jaws are secured together, the jaws are held against independent endwise movement, and the outer ends thrown open when the sleeve is turned outward and closed together and the bases left free to adapt themselves to a tool-shank when the sleeve is turned inward.

In a brace-chuck, a U-shaped spring, in combination with jaws having openings in their bases through which the base of the spring passes, and recesses in their backs to receive the arms of the spring when the bases of the jaws are opened.

In testin'iony whereof I at'fix my signature in presence of two witnesses.

JOHN S. FRAY. \Vitncsses:

A. M. WoosTER, BERTHA E. LEE. 

